Benzoyl chromate

Similar to aminolysis, the alcoholysis reaction can be applied to the synthesis of higher nuclearity metal carbenes as well. Low-temperature addition of 0.4 equivalents of pentaerythritol in DMF to a solution of chromium acetoxycarbene generated in situ from benzoyl chromates 133 (or 134) affords moderate yields of tetra-kischromium carbene 135 (or 136) which undergoes complete benzannulation with 3-hexyne to give an 80% yield of the spherical tetrakishydroquinone 137 after in situ protection of the naphthol intermediate with TBDMSCl and subsequent oxidative demetallation (Scheme 11.32) [57]. 

Aluminum chlorate Ammonium chromate Benzoyl peroxide, dry... 

CrFeN09P2C45H3i, Chromate(l -)hydrido-nonacarbonyliron-, p.-nitrido-bis(tri-phenylphosphorus)(l -(-), 26 338 CrFeN209P4C,iH i, Chromate(2-), nona-carbonyliron-, bis[p.-nitrido-bis(tri-phenylphosphorus)(l +)], 26 339 CrNOsCwH, Chromium, (benzoyl isocyan-ide)dicarbonyl(T -methyl benzoate)-, 26 32... 

Bisphenol-A diphenyl phosphate Benzoyl peroxide Butadiene rubber Butadiene styrene rubber Cellulose acetate Clean Air Act Cellulose acetate butyrate Cellulose acetate propionate Chemical Abstracts Service Chromated copper arsenate... 

Labeled compounds. A mixture of 4-(cyanobenzyl) benzanthrone- C, Na-di-chromate, Na-acetate, and glacial acetic acid heated 3hrs. on a steam bath -> 4-benzoyl-7H-benz[de]anthracen-7-one-7,12- C. Y 84%. E. Boger and P. Bernfeld, J. Labelled Compds. 1, 109 (1965). 

The same type of reactions can be conducted with methyl 2,3,6-tri-O-benzoyl-4-0-trifyl a-D-glucopyranoside to give modified D-galactoses. The free 4-hy-droxyl-carbon can be oxidized with pyridinium chromate to produce the 4-keto derivative, which, in turn, can be fluorinated with DAST to provide the 4-g m-di-fluoride (reaction 4.113). 

Sucrose can be selectively oxidized at C-6 by reacting 2,3,4,l, 3, 4, 6 -hepta-6>-benzoyl sucrose with pyridinium chromate to convert C-6 into an aldehyde. The aldehyde group can be reduced with sodium borohydride to create specifically labeled 6-pH]sucrose (reaction 4.135). 

NCrFe09P2C49H3, Chromate(l—X hydri-dononacarbonyliron-, p-nitrido-bis(triphenylphosphorus)(l +), 26 338 NCr03C7H], Chromium, dicarbonyl(> -cyclopentadienyl)nitrosyl-, 28 196 NCr03CiiH,i, Chromium, tricarbonyl(q -N,AI-dimethylbenzenamine)-, 28 139 NCrOgCioHj, Chromium, (tert-butyl isocyanide)pentacaibonyl-, 28 143 NCrOgCiiHig, Chromium, (benzoyl isocyamde)dicarbonyl(i -methyl benzoatcK 26 32... 

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